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\IBVShead{4226}{10 August 1995}

\centerline{\ft PRECISION B,V,R,I LIGHT CURVES AND NEW}
\centerline{\ft DETERMINATION FOR V440 CASSIOPEIAE}
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\begintext



    V440 Cassiopeiae was discovered by Hoffmeister (1967), and classified as an 
Algol variable.  His paper includes accurate positions, a finder chart, three 
times of minimum light, and maximum and minimum magnitudes. Busch and H\"aussler
(1990) observed V440 Cas, reclassifying it as a W UMa type.  They listed 
maximum and minimum magnitudes and calculated the ephemeris
\vskip 1mm
 \hspace*{4cm}   Min. I = J.D.\,2447391.555 + 0\fd 280692 $\times$ E  \hfill  (1)
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However, their light curve is either extremely noisy or improperly phased.  
Aside from these two papers, V440 Cas has apparently been ignored.

    Our present observations were made on 27, 28, and 29 September 1994  at 
Kitt Peak National Observatory, Arizona, with the CCD photometer system 
(CCDPHOT) in conjunction with the 0.9 m Cassegrain reflector telescope.  
Approximate coordinates of the variable, comparison and the check star are 
given in Table 1 and are designated as star V, C, and K, respectively, on our 
CCD image (Figure 1).  About 250 observations were taken in each passband, B, 
V, R, I.

    Five mean epochs of minimum light were determined from observations 
made during three secondary and two primary eclipses. The bisection of chords 
technique was used in their determination.  Our minima are given in Table 2 
along with those by Hoffmeister (1967) and the epoch by Busch and 
H\"aussler (1990).  Timings are accompanied by their probable errors in 
parentheses. These were introduced into a weighted least squares 
solution to obtain the following linear ephemeris: 
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\hspace*{3cm}JD Hel Min. I = J.D.\,2449624.797 + 0\fd 3256880 $\times$ E \hfill (2)

\hspace*{8.6cm}$\pm$3 \hspace*{10mm} \ \ \ \ $\pm$3
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In this calculation, Hoffmeister's times were given a weight of 
0.1, while our minima and the epoch by Busch and H\"aussler were assigned 
weights of 1.0.  On 28 September, our observations covered a complete light 
curve affirming our new period. Thus, the 0.28 day period given by Busch and 
H\"aussler is in error, probably due to aliasing.  The major source of 
uncertainty in the above empheris arises from the low precision of the 
previous timings.  If timings reported by Hoffmeister are excluded from the 
analysis, the following improved ephemeris is obtained:
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\hspace*{3cm}JD Hel Min. I = J.D.\,2449624.79708 + 0\fd 32568791 $\times$ E \hfill  (3)
\hspace*{9.5cm}$\pm$8 \hspace*{14mm}\ \ \ \ \,$\pm$3
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The residuals calculated from equation 2 are listed in Table 2 as (O$-$C)$_1$, while the residuals of equation 3 are listed as (O$-$C)$_2$.

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\centerline{2}
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Figure 1. Finder Chart for V440 Cas.  The stars marked "V", "C", and "K" are V440 Cas, the comparison star, and the check star, respectively.
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\centerline{Table 1}
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\begin{center}
\begin{tabular}{lcc}
\hline
                Star     &    R. A. (2000)   &      Dec. (2000)\\
\hline
\\
              V440 Cas  &      23\fh 36\fmm 40\fs &  51\degr 09' 29''\\
              Comparison &     23\fh 36\fmm 46\fs &  51\degr 10' 35''\\
              Check    &       23\fh 36\fmm 36\fs &  51\degr 10' 38''\\
\hline
\end{tabular}
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 \centerline{Table 2}
\begin{center}
\begin{tabular}{lrrcc}
\hline
       JD Hel. 2400000+  &  Cycles& (O$-$C)$_1$&(O$-$C)$_2$ & Source\\
 \hline
\\                           
              29193.42  &    $-$62733.0 & +0.0072 & +0.0033 &    HO\\     
              30253.34  &    $-$59478.5 & $-$0.0244 &$-$0.0280  &   HO \\
              30262.50   &   $-$59450.5 & +0.0164 & +0.0127 &    HO \\
              47391.555   &   $-$6857.0 & +0.0004 & +0.0000 &    BH \\
              49623.6574(8)&     $-$3.5 & +0.0001 & +0.0002 &    PO   \\   
              49623.8196(5)&     $-$3.0  &$-$0.0005 &$-$0.0004  &   PO\\
              49623.9828(5)&     $-$2.5 & $-$0.0001 & $-$0.0001 &    PO\\
              49624.6345(3)&     $-$0.5 & +0.0002 & +0.0003 &    PO\\
              49624.7971(1)&      0.0 & $-$0.0001 & $-$0.0000 &    PO\\
\hline

\end{tabular}
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PO=Present Observations, BH=Busch and H\"aussler (1990), HO=Hoffmeister (1967)
   
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\centerline{3}
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Figure 2.  Photoelectric light curves in B and V of V440 Cas as defined by the
individual observations.
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Figure 3.  Photoelectric light curves in R and I of V440 Cas as defined by the
individual observations.
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    More timings of minimum light are needed to determine the period behavior 
of this binary.

    The B, V  light curves of V440 Cas are shown in Figure 2, and the R, I light 
curves are shown in Figure 3.  All light curves shown are as defined by 
individual observations and presented as differential magnitude (v$-$c) versus 
phase.  Our light curves confirm Busch and H\"aussler's classification of V440 
Cas as a W UMa variable.  The analysis of the observations is underway.

        Much of the present analysis was performed by JF as a part of her
undergraduate summer research project, funded through the American 
Astronomical Society REU program.
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\beginauthors
\authorsrightcol
Ronald G. SAMEC$^{1,\,2}$, 
Brian CARRIGAN$^2$, and 
Julie FRENCH$^1$
Millikin University         
Decatur, IL 62522 USA
\endauthors

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\noindent $^1$ This research was partially supported by funds from the National
Science Foundation.
  
\noindent $^2$ Visiting Astronomer, Kitt Peak National observatory, National 
Optical Astronomical Observatories, which are operated by the Association of 
Universities for Research in Astronomy, Inc. under contract with the National 
Science Foundation.

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\references

Hoffmeister, C., 1967, {\it AN}, {\bf 290}, 1-2, 43

Busch, H., and H\"aussler, K., 1990, {\it VSS}, {\bf 10},  4,  354

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